1. Field of the Invention
The present invention relates to an image pickup system comprising a signal processing device in which an exclusive adaptor is mounted on a body of the signal processing device in accordance with probes such as those used in electronic scopes or the like, whereby the signal processing device is capable of processing a signal with respect to probes which have different image pickup systems.
2. Description of the Related Art
In recent years, an endoscope has widely been used in which elongated inserting section is inserted into a body, Whereby an affected or diseased part or the like illuminated from a forward end of the inserting section is observable by light which is taken or fetched thereinto through an objective lens provided on an observation window.
Further, an electronic endoscope system has also been put to practical use wherein an electronic endoscope is used in which an image pickup element such as a CCD or the like is arranged on a focal surface or plane of an objective lens, and a signal photoelectrically transferred by the image pickup element is processed by a signal processing device, whereby an image of a subject can be displayed on a monitor.
In a case of the electronic endoscope, if the numbers of picture elements of the image pickup devices differ from each other, it is necessary to also replace or change the signal processing of the signal processing device. As a prior art example, Japanese Patent Laid-Open No. SHO 63-260527 (260527/1988) discloses an electronic endoscope system in which a signal processing device section is unitized in correspondence to the number of picture elements of the electronic endoscope, and an exclusive unit is mounted on and is used in accordance with electronic endoscopes different in the number of picture elements from each other, whereby the electronic endoscope system can cope with electronic endoscopes differing from each other in the number of picture elements.
However, in the image pickup system of the electronic endoscope, there exist a concurrent type in which a color image is produced under white light illumination, and also a surface sequential type in which image pickup is performed under surface sequential illuminating light which performs sequential illumination by illuminating lights differing from each other in wavelength regions to produce a color image. The above-described prior art can deal with a case where just the number of picture elements differ from each other, but cannot deal with a case where the image pickup systems themselves are different from each other.
In a case where the image pickup systems are different from each other, replacement of the entire signal processing device is expensive. Accordingly, a system is desired which can deal also with a case where the image pickup systems are different from each other, at low cost.
Therefore, it is desirable to utilize a system which can selectively use electronic endoscopes having image pickup systems which differ from each other in regard to the status or circumstances of performance of inspection/diagnosis. Accordingly, more efficient endoscope inspection/diagnosis is made possible.
For example, when the type of endoscope is used in which the color image is produced under the white illumination, color shear generation is minimized even in a case where a subject large in motion is image-picked-up. Accordingly, the concurrent type is effective in a case where an internal organ in the vicinity of a heart is inspected/diagnosed.
On the other hand, in a case .Where an internal organ remote from the heart or within a narrow lacuna in which motion or movement is minimal is inspected/diagnosed, if the surface sequential type is utilized, there is produced an endoscope image which has resolution of the order of three (3) times greater than the case of the concurrent type (it is assumed that the image pickup elements the same in size as each other are used both in the concurrent type and in the surface sequential type). Accordingly, an abnormal portion can be discriminated in detail.
On the other hand, in a case where an internal organ adjacent to the heart is inspected/diagnosed, if only the electronic endoscope of surface sequential type is used, there is a possibility that an image is brought to an endoscope image in which there is a significant amount of color shear. In this case, even if the electronic endoscope different in the number of picture elements from the previous endoscope is used, as in the prior art, an improvement cannot be expected.
Moreover, in a case where a part within the narrow lacuna is inspected/diagnosed, if only the electronic endoscope which provides a color image under white light illumination is used, it becomes difficult to produce an image high in resolution. In this case, if the electronic endoscope large or high in the number of picture elements is used, the resolution is improved. However, since the size of an image pickup element also increases, it becomes difficult to insert the electronic endoscope into the narrow lacuna.
Accordingly, in order to produce more effective endoscope inspection/diagnose results, it is desirable to realize, at low cost, a system also selectively used among various electronic endoscopes which differ from each other in their image pickup systems, as described previously.
Furthermore, the above-described prior art cannot cope with a case of a system which can selectively use the electronic endoscope and an ultrasonic scope capable of producing an ultrasonic image which is different in kind or type from an image in which an optical image due to the electronic endoscope is photoelectrically transferred.
If the system is an image pickup system which can be used also in the ultrasonic scope in which acoustic image information different from optical image information due to the electronic endoscope can be reduced with respect to an inspection object such as an affected or diseased part or the like, more effective information in a case of inspection/diagnoses can be produced.
Further, if the system can change a system arrangement at low cost from the electronic endoscope system as occasion demands, to a system arrangement suitable for inspection/diagnoses, the system becomes extremely effective in performing inspection/diagnoses.